How It Works - UK (2020-02)

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SPACE

W

hen you think of a telescope, you

probablyimaginesomesortoftube

witha largelensusedtopeerdeep

intotheuniverse.ButtheSquareKilometre

Array(SKA)issomethingentirelydifferent.It

willuseantennaewitha collectingareaof

aboutonesquarekilometretoproberadio

wavesfromtheuniverselikeneverbefore,and

perhapsgiveusourbest-everglimpseinto

someofitsearliestmoments.

TheSKAisbeingbuiltprimarilyintwo

locations,oneinAustraliaandtheother

inSouthAfrica,alongwithseveralother

smallerinstallationsinothercountries.The

locationshavebeenchosenastheyarefar

fromhumaninfrastructure,meaningthe

antennaecanobservetheuniverse’sradio

wavesaroundtheclockwithoutinterference

fromterrestrialsignals.

Withcontributionsfrom 20 countriesin

total,headquarteredatJodrellBankinthe

UKandsettobeginoperationsin2024,the

SKAwillbethelargestradiotelescopeever

How the Square Kilometre Array project will

probe the secrets of the universe

What will the world’s

biggest telescope see?

Words by Jonathan O’Callaghan

©SPDO/TDP/DRAO/Sw

nburne

Astronomy

Product

ons

Mission goals Whatdoestheprojecthopetodiscover?

built. Together its thousands of antennae will

be spread over an area of about a continent,

making it 50 times more sensitive and 10,000

times faster at surveying the sky than any

other telescope.

The project is expected to cost £1.3 billion

and is being built in two phases, called

SKA1-Low and SKA2-Mid. In 2027 the project

will begin its full operation, using more than

TheDarkAges

TheSKAwilllookback

towhenthefirststars

andblackholes

formedin a period

calledtheDarkAges,

a timewhenthere

wasverylittlelight

leftoverin the

universeafterthe

BigBang.

©NASA/WMAP

Sc

ence

Team

Structureof

theuniverse

Byobservingtheflow

ofhydrogenbetween

galaxies,theSKAwill

examinethe

large-scalestructure

oftheuniverse,

thoughttobe

dominatedby

darkenergy.

© Max Planck Institute For Astrophysics

Magnetic

fields

TheSKAwillstudythe

rolethatmagnetic

fieldsplayin the

formationand

evolutionofstarsand

galaxiesbyobserving

theradiowaves

emittedbyelectronsin

thesefields.

© NASA/SDO/AIA/LMSAL

Searchforlife

With its vast radio

power, the SKA will

look for any radio

signals being

emitted from other

planets. If found,

these could be an

indicator of advanced

alien life somewhere

in the universe.

©ESA/Hubb

eM

Kornmesser

General

relativity

Rapidly spinning stars

called pulsars detected

by the SKA will allow

scientists to probe

Einstein’s theories of

gravity. Pulsars can

also help hunt for

gravitational waves in

the early universe.

© NASA’s Goddard Space Flight Center

“The antennae can

observe the universe’s

radio waves around

the clock”

100,000 antennae in total. Among its science

goals, the SKA will probe Einstein’s theory of

general relativity, observe how galaxies evolve

and even look for signals of advanced

extraterrestrial life in other solar systems.

All told, this is one of the most ambitious

astronomy projects attempted in the history of

humanity – and in just a few years we might be

reaping its vast science benefits.

Thousands of radio dishes are spread

out across several continents